Swift 4.2 code equivalent for SAP's Leonardo API [duplicate] - swift

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Upload image with parameters in Swift
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Closed 4 years ago.
Getting HTTP 400 error while connecting with SAP Leonardo sandbox server using scene text recognition API
SAP provides boilerplate code in older version of swift. I have used curl command and the API and works. But its not working when I try and convert the code into swift 4.2 version. I am attaching the code below.
func connectWithSAP(photoURL : URL, photoData : String, sentImageData : Data){
if let myNewURL = URL(string: "https://sandbox.api.sap.com/ml/scenetextrecognition/scene-text-recognition") {
var myRequest = URLRequest(url: myNewURL)
myRequest.addValue("multipart/form-data; --\(boundary)", forHTTPHeaderField: "Content-Type")
myRequest.addValue("application/json", forHTTPHeaderField: "Accept")
myRequest.addValue("xxxxxxxxxxx", forHTTPHeaderField: "APIKey")
myRequest.httpMethod = "POST"
myRequest.cachePolicy = .reloadIgnoringLocalCacheData
myRequest.timeoutInterval = 60.0
// Constructing the body of the request.
var data = Data()
var dataString = ""
dataString.append("--\(boundary)\r\n")
dataString.append(contentsOf: "Content-Disposition:form-data; name=\"files\"; filename=\"Image1.jpeg\" \r\n")
dataString.append(contentsOf: ";Content-Type:image/jpeg \r\n\r\n")
dataString.append(photoData)
dataString.append("--\(boundary) ----- \r\n")
data = dataString.data(using: .utf8)!
myRequest.httpBody = data
let task = URLSession.shared.dataTask(with: myRequest) { (data, response, error) in
if let error = error {
print(error)
}
guard let httpResponse = response as? HTTPURLResponse,
(200...299).contains(httpResponse.statusCode) else {
print(error as Any)
// Getting output at this stage, which is shown below
return }
if let mimeType = httpResponse.mimeType,
mimeType == "application/json",
let data = data {
do {
let json = try JSONSerialization.jsonObject(with: data, options: []) as? [String:Any]
print(json as Any)
}catch {
print(error)
}
}
}
task.resume()
}
I am getting a following details in my response object
{ URL: https://sandbox.api.sap.com/ml/scenetextrecognition/scene-text-recognition } { Status Code: 400, Headers {\n Connection = (\n \"keep-alive\"\n );\n \"Content-Length\" = (\n 131\n );\n \"Content-Type\" = (\n \"application/json\"\n );\n Date = (\n \"Sat, 16 Feb 2019 11:56:37 GMT\"\n );\n Server = (\n \"Werkzeug/0.14.1 Python/3.5.5\"\n );\n \"Strict-Transport-Security\" = (\n \"max-age=31536000; includeSubDomains; preload;\"\n );\n \"X-Vcap-Request-Id\" = (\n \"fea7037c-4e48-49d2-4be1-53b0dad0ee46\"\n );\n}
As you would see the status code is HTTP 400. Need some help in getting the right response and data from the server.

Answer 1

Most probably, the body data got messed up. Here's the working code:
let boundaryConstant = "----WebKitFormBoundary7MA4YWxkTrZu0gW"
let headers = [
"APIKey": "YourAPIKEY"
]
let contentType = "multipart/form-data; boundary=" + boundaryConstant
//API endpoint for API sandbox
var request = URLRequest(url: URL(string: "https://sandbox.api.sap.com/ml/scenetextrecognition/scene-text-recognition")!)
//setting request method
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
let session = URLSession.shared
let path1 = Bundle.main.path(forResource: "your_image", ofType: "png")!
let url = URL(fileURLWithPath: path1)
let fileName = url.lastPathComponent
let data = try? Data(contentsOf: url)
let imageData = UIImage.init(data: data!)!
let pngData = UIImagePNGRepresentation(imageData)!
let mimeType = "image/png"
let boundaryStart = "--\(boundaryConstant)\r\n"
let boundaryEnd = "--\(boundaryConstant)--\r\n"
let fieldName = "files"
let contentDispositionString = "Content-Disposition: form-data; name=\"\(fieldName)\"; filename=\"\(fileName)\"\r\n"
let contentTypeString = "Content-Type: \(mimeType)\r\n\r\n"
var body = Data()
body.append(boundaryStart.data(using: .utf8)!)
body.append(contentDispositionString.data(using: .utf8)!)
body.append(contentTypeString.data(using: .utf8)!)
body.append(pngData)
body.append("\r\n".data(using: .utf8)!)
body.append(boundaryEnd.data(using: .utf8)!)
request.httpBody = body
request.setValue(contentType, forHTTPHeaderField: "Content-Type")
request.setValue(String(body.count), forHTTPHeaderField: "Content-Length")
let dataTask = session.dataTask(with: request) { (data, response, error) in
if (error != nil) {
print(error)
} else {
let httpResponse = response as? HTTPURLResponse
print(httpResponse)
}
}
dataTask.resume()
You can also use Alamofire to upload image. It's way cleaner, don't need to play around with "body" much:
let headers: HTTPHeaders = [
"APIKey": "<<Your API KEY>>",
"Content-type": "multipart/form-data"
]
let parameters:[String: String] = [:] //any other parameters you need to send
let path1 = Bundle.main.path(forResource: "<<your_image>>", ofType: "<<png or jpeg>>")!
let url = URL(fileURLWithPath: path1)
let fileName = url.lastPathComponent
let data = try? Data(contentsOf: url)
let imageData = UIImage.init(data: data!)!
//converting it into png data
let pngData = UIImagePNGRepresentation(imageData)
let mimeType = "image/png"
let fieldName = "files"
Alamofire.upload(multipartFormData: { (multipartFormData) in
for (key, value) in parameters {
multipartFormData.append("\(value)".data(using: String.Encoding.utf8)!, withName: key as String)
}
if let data = pngData{
multipartFormData.append(data, withName: fieldName, fileName: fileName, mimeType: mimeType)
}
}, usingThreshold: UInt64.init(), to: "https://sandbox.api.sap.com/ml/scenetextrecognition/scene-text-recognition" , method: .post, headers: headers) { (result) in
switch result{
case .success(let upload, _, _):
upload.responseJSON { response in
print("Succesfully uploaded")
}
case .failure(let error):
print("Error in upload: \(error.localizedDescription)")
}
}